Eirmotus, Kottelat, 2008

Kottelat, Tan Heok Hui Maurice, 2008, Revision Of The Cyprinid Fish Genus Eirmotus, With Description Of Three New Species From Sumatra And Borneo, Raffles Bulletin of Zoology 56 (2), pp. 423-433 : 424

Key to the species of Eirmotus

1a. Black pigmentation along simple dorsal rays restricted to anterior two rays and proximal half of third ray, fainter grey distally; a row of faint black spots at about 2/3 of branched dorsal rays, sometimes extending on membranes .................... E. insignis

1b. Black pigmentation along simple dorsal rays extending on entire length of rays; no black marks on middle of dorsal fin ...... 2

2a. Mouth subinferior, upper lip entirely distinct in ventral view; lower jaw pointed anteriorly; bars narrow (width of bar 5 equal to half of lateral row scale) ................................... E. isthmus

2b. Mouth terminal, upper lip not entirely distinct in ventral view; lower jaw wide, anteriorly rounded; bars wide (width of bar 5 equal to one to two lateral row scales) ................................ 3

3a. Black marks on body wide, very conspicuous and contrasted; all fins dusky with scattered chromatophores on all rays; distinct black mark situated at posterior tip of dorsal fin, appearing as part of bar 6; in adults, all simple rays of anal fin black on entire length; 17–21 serrae along posterior edge of last simple dorsal ray ................................................................. E. furvus

3b. Black marks on body narrow and not sharply contrasted; fins hyaline; dorsal fin hyaline, in a few specimens with diffuse chromatophores on last ray, adjacent to bar 6; in adults, anterior rays of anal fin black at base only; 25–31 serrae along posterior edge of last simple dorsal ray ............................. E. octozona